Over the many years, there has long existed the problem of land erosion adjacent waterways, rivers, lakes and oceans wherein seawalls of various types have heretofore been constructed of wood, steel or cement. Heretofore, efforts have been made to provide a series of seawall elements which are laterally aligned and in some manner interconnected and pounded down into the ground and anchored. Illustrative of earlier prior art efforts to provide a seawall, constructed of reinforced concrete, is U.S. Pat. No. 1,332,655 issued to R. B. Willard in 1920. The problem then as recognized by the inventor and thereafter, has been the enormous pressures and loads applied to the seawall which have ultimately destroyed the connection between adjacent seawall elements to render the seawall less than effective and ultimately requiring replacement and repairs.
It is known to form seawalls of a plurality of panels formed of extruded PVC material and interconnected edge to edge, as shown in Berger, U.S. Pat. Nos. 4,674,921 issued Jun. 23, 1987 and 4,690,588 issued Sep. 1, 1987. In Berger, panel strips of corrugated or sinusoidal shape are formed with alternating groove edges and tongue edges, permitting the panels to be interlocked along their vertical marginal edges. Wale elements are mounted along outer surfaces of the panel strips and accept tie bolts or tie rods extending to ground anchors on the opposite side of the seawall. Berger also discloses angled strips for making corners, and connectors for joining adjacent strips in edge-to-edge relation.
Sinusoidal or corrugated sheets have been mounted in facing relation and connected or joined by tie rods, and the spaces therebetween have been filled with concrete or mortar to provide a water-tight joint, to form a revetment, as shown in Schneller, U.S. Pat. No. 3,247,673 of Apr. 26, 1966.
Sinusoidal or corrugated panel sections have been used to make up retaining walls or seawalls, with wale elements on a front surface tied back to anchors, as shown in a number of prior patents. Caples, U.S. Pat. No. 1,947,151 of Feb. 13, 1934 shows panel sections formed with interconnecting locking vertical edges in alternating inwardly and outwardly directed portions to form a sinusoidal wall. In Caples, the interlocking ends are identical. In Frederick, U.S. Pat. No. 3,822,557 of Jul. 9, 1974, one panel vertical edge is formed with a tongue and the opposite panel vertical edge is formed with a groove proportioned to receive the tongue of an adjacent panel.
Another example of a retaining wall made of interlocking sections of sheet material is McGrath, U.S. Pat. No. 2,968,931 of Jan. 24, 1961. In McGrath each panel section is bent into three angular portions, and each panel section is reversed when connected, edge to edge to form a sinusoidal-like pattern.
Earlier examples of wall systems having interlocking panel sections which are assembled in longitudinal alignment, with interlocking vertical edges, include Clarke, U.S. Pat. No. 972,059 of Oct. 4, 1910; Boardman et al, U.S. Pat. No. 1,422,821 of Jul. 18, 1922; and Stockfleth, U.S. Pat. No. 1,371,709 of Mar. 15, 1921.
It is also known to use a series of individual arcuate sections which are then joined or interconnected to form a retainer wall, as shown in Van Weele, U.S. Pat. No. 4,407,612 of Oct. 4, 1983.
While walls formed by corrugated panel sections are extensively shown in the prior art in which the corrugations or the axes of the corrugations run vertically, is also known to form panel sections in which the axes of the corrugations run horizontally, as shown in Sivachenko U.S. Pat. No. 4,099,359 of Jul. 11, 1978. FIGS. 7 and 8 also show opposed facing pairs of corrugated sections in which the spaces therebetween may be filled with concrete to form a revetment.
It is common to use wale brackets or wale elements in combination with panel-type seawalls or retainer walls. Berger, Schnabel, Jr. and Caples show wale elements in longitudinal alignment. Schnabel, Jr., U.S. Pat. No. 3,541,798 of Nov. 24, 1970 shows individual longitudinally spaced wale elements along the wall front face. The wale elements receive tie-back rods, which rods extend through or between the panels to suitable anchors.
Essentially two-dimensional polymeric retaining wall members with interlocking members along the edges that are universally mateable to like members are illustrated in U.S. Pat. No. 4,863,315, issued Sep. 5, 1989 to Wickberg while a wall system which employs a plurality of individual panels formed of extruded polymer joined in edge-to-edge relation including wale members which are vertically offset and interlocked at end portions thereof with adjacent wale members is shown in U.S. Pat. No. 4,917,543, issued Apr. 17, 1990 to Cole et al.
A shoreline erosion prevention bulkhead system which employs a series of interlocking fiberglass panels is shown in U.S. Pat. No. 5,066,353 issued Nov. 19, 1991, to Bourdo while a plastic structural panel and ground erosion barrier is illustrated which in general is a stretched Z-shaped cross-sectional design with opposed male and female interlock edges for mating association with adjacent panel strips in U.S. Pat. No. 5,145,287 issued Sep. 8, 1992 to Hooper et al.
Corner adapters for use with corrugated barrier sections are disclosed in U.S. Pat. No. 5,292,208 issued Mar. 8, 1994 to Berger and a sheet piling extrusion with locking members is illustrated in U.S. Pat. No. 6,000,883 to Irving et al. A reinforced Z-shaped configuration of the same with strengthening ribs is illustrated in U.S. Pat. No. 6,033,155 issued Mar. 7, 200 to Irvine et al. A generally U-shaped seawall panel is disclosed in U.S. Pat. No. 6,575,667 issued Jun. 10, 2003 to Burt et al.
This invention was developed to continue to advance the state-of-the-art for retaining walls, particularly extruded polyvinyl chloride (PVC) retaining walls which offer easier installation and greater structural integrity than those found in the Prior Art.